* Heavily rewritten.
*/
+#include <linux/config.h>
#include <linux/syscalls.h>
#include <linux/slab.h>
#include <linux/sched.h>
static int event;
-static struct list_head *mount_hashtable __read_mostly;
+static struct list_head *mount_hashtable;
static int hash_mask __read_mostly, hash_bits __read_mostly;
-static kmem_cache_t *mnt_cache __read_mostly;
+static kmem_cache_t *mnt_cache;
static struct rw_semaphore namespace_sem;
/* /sys/fs */
return mnt;
}
-int simple_set_mnt(struct vfsmount *mnt, struct super_block *sb)
-{
- mnt->mnt_sb = sb;
- mnt->mnt_root = dget(sb->s_root);
- return 0;
-}
-
-EXPORT_SYMBOL(simple_set_mnt);
-
void free_vfsmnt(struct vfsmount *mnt)
{
kfree(mnt->mnt_devname);
.show = show_vfsmnt
};
-static int show_vfsstat(struct seq_file *m, void *v)
-{
- struct vfsmount *mnt = v;
- int err = 0;
-
- if (vx_flags(VXF_HIDE_MOUNT, 0))
- return 0;
- if (!mnt_is_reachable(mnt) && !vx_check(0, VX_WATCH))
- return 0;
-
- if (!vx_check(0, VX_ADMIN|VX_WATCH) &&
- mnt == current->fs->rootmnt) {
- seq_puts(m, "device /dev/root mounted on / ");
- } else {
- /* device */
- if (mnt->mnt_devname) {
- seq_puts(m, "device ");
- mangle(m, mnt->mnt_devname);
- } else
- seq_puts(m, "no device");
-
- /* mount point */
- seq_puts(m, " mounted on ");
- seq_path(m, mnt, mnt->mnt_root, " \t\n\\");
- seq_putc(m, ' ');
- }
-
- /* file system type */
- seq_puts(m, "with fstype ");
- mangle(m, mnt->mnt_sb->s_type->name);
-
- /* optional statistics */
- if (mnt->mnt_sb->s_op->show_stats) {
- seq_putc(m, ' ');
- err = mnt->mnt_sb->s_op->show_stats(m, mnt);
- }
-
- seq_putc(m, '\n');
- return err;
-}
-
-struct seq_operations mountstats_op = {
- .start = m_start,
- .next = m_next,
- .stop = m_stop,
- .show = show_vfsstat,
-};
-
/**
* may_umount_tree - check if a mount tree is busy
* @mnt: root of mount tree
spin_unlock(&vfsmount_lock);
if (actual_refs > minimum_refs)
- return 0;
+ return -EBUSY;
- return 1;
+ return 0;
}
EXPORT_SYMBOL(may_umount_tree);
*/
int may_umount(struct vfsmount *mnt)
{
- int ret = 1;
+ int ret = 0;
spin_lock(&vfsmount_lock);
if (propagate_mount_busy(mnt, 2))
- ret = 0;
+ ret = -EBUSY;
spin_unlock(&vfsmount_lock);
return ret;
}
{
struct vfsmount *p;
- for (p = mnt; p; p = next_mnt(p, mnt))
- list_move(&p->mnt_hash, kill);
+ for (p = mnt; p; p = next_mnt(p, mnt)) {
+ list_del(&p->mnt_hash);
+ list_add(&p->mnt_hash, kill);
+ }
if (propagate)
propagate_umount(kill);
*/
lock_kernel();
- if (sb->s_op->umount_begin)
- sb->s_op->umount_begin(mnt, flags);
+ if ((flags & MNT_FORCE) && sb->s_op->umount_begin)
+ sb->s_op->umount_begin(sb);
unlock_kernel();
/*
}
}
-/*
- * go through the vfsmounts we've just consigned to the graveyard to
- * - check that they're still dead
- * - delete the vfsmount from the appropriate namespace under lock
- * - dispose of the corpse
- */
-static void expire_mount_list(struct list_head *graveyard, struct list_head *mounts)
-{
- struct namespace *namespace;
- struct vfsmount *mnt;
-
- while (!list_empty(graveyard)) {
- LIST_HEAD(umounts);
- mnt = list_entry(graveyard->next, struct vfsmount, mnt_expire);
- list_del_init(&mnt->mnt_expire);
-
- /* don't do anything if the namespace is dead - all the
- * vfsmounts from it are going away anyway */
- namespace = mnt->mnt_namespace;
- if (!namespace || !namespace->root)
- continue;
- get_namespace(namespace);
-
- spin_unlock(&vfsmount_lock);
- down_write(&namespace_sem);
- expire_mount(mnt, mounts, &umounts);
- up_write(&namespace_sem);
- release_mounts(&umounts);
- mntput(mnt);
- put_namespace(namespace);
- spin_lock(&vfsmount_lock);
- }
-}
-
/*
* process a list of expirable mountpoints with the intent of discarding any
* mountpoints that aren't in use and haven't been touched since last we came
*/
void mark_mounts_for_expiry(struct list_head *mounts)
{
+ struct namespace *namespace;
struct vfsmount *mnt, *next;
LIST_HEAD(graveyard);
list_move(&mnt->mnt_expire, &graveyard);
}
- expire_mount_list(&graveyard, mounts);
-
- spin_unlock(&vfsmount_lock);
-}
-
-EXPORT_SYMBOL_GPL(mark_mounts_for_expiry);
-
-/*
- * Ripoff of 'select_parent()'
- *
- * search the list of submounts for a given mountpoint, and move any
- * shrinkable submounts to the 'graveyard' list.
- */
-static int select_submounts(struct vfsmount *parent, struct list_head *graveyard)
-{
- struct vfsmount *this_parent = parent;
- struct list_head *next;
- int found = 0;
-
-repeat:
- next = this_parent->mnt_mounts.next;
-resume:
- while (next != &this_parent->mnt_mounts) {
- struct list_head *tmp = next;
- struct vfsmount *mnt = list_entry(tmp, struct vfsmount, mnt_child);
-
- next = tmp->next;
- if (!(mnt->mnt_flags & MNT_SHRINKABLE))
- continue;
- /*
- * Descend a level if the d_mounts list is non-empty.
- */
- if (!list_empty(&mnt->mnt_mounts)) {
- this_parent = mnt;
- goto repeat;
- }
-
- if (!propagate_mount_busy(mnt, 1)) {
- mntget(mnt);
- list_move_tail(&mnt->mnt_expire, graveyard);
- found++;
- }
- }
/*
- * All done at this level ... ascend and resume the search
+ * go through the vfsmounts we've just consigned to the graveyard to
+ * - check that they're still dead
+ * - delete the vfsmount from the appropriate namespace under lock
+ * - dispose of the corpse
*/
- if (this_parent != parent) {
- next = this_parent->mnt_child.next;
- this_parent = this_parent->mnt_parent;
- goto resume;
- }
- return found;
-}
-
-/*
- * process a list of expirable mountpoints with the intent of discarding any
- * submounts of a specific parent mountpoint
- */
-void shrink_submounts(struct vfsmount *mountpoint, struct list_head *mounts)
-{
- LIST_HEAD(graveyard);
- int found;
+ while (!list_empty(&graveyard)) {
+ LIST_HEAD(umounts);
+ mnt = list_entry(graveyard.next, struct vfsmount, mnt_expire);
+ list_del_init(&mnt->mnt_expire);
- spin_lock(&vfsmount_lock);
+ /* don't do anything if the namespace is dead - all the
+ * vfsmounts from it are going away anyway */
+ namespace = mnt->mnt_namespace;
+ if (!namespace || !namespace->root)
+ continue;
+ get_namespace(namespace);
- /* extract submounts of 'mountpoint' from the expiration list */
- while ((found = select_submounts(mountpoint, &graveyard)) != 0)
- expire_mount_list(&graveyard, mounts);
+ spin_unlock(&vfsmount_lock);
+ down_write(&namespace_sem);
+ expire_mount(mnt, mounts, &umounts);
+ up_write(&namespace_sem);
+ release_mounts(&umounts);
+ mntput(mnt);
+ put_namespace(namespace);
+ spin_lock(&vfsmount_lock);
+ }
spin_unlock(&vfsmount_lock);
}
-EXPORT_SYMBOL_GPL(shrink_submounts);
+EXPORT_SYMBOL_GPL(mark_mounts_for_expiry);
/*
* Some copy_from_user() implementations do not return the exact number of
}
}
-EXPORT_SYMBOL_GPL(set_fs_root);
-
/*
* Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values.
* It can block. Requires the big lock held.
git://git.onelab.eu / linux-2.6.git / blobdiff